A connector used to electrically connect a circuit board and an electrical wire on an automobile is required to have as small dimensions as possible in both the vertical and horizontal directions, such that it has as small of height and width (pitch) as possible. The applicant has proposed in Japanese Patent Laid-Open No. 2007-324049 a connector that provides a sufficient contact holding force while meeting the requirement.
The connector disclosed in Japanese Patent Laid-Open No. 2007-324049 includes a housing having a front, a rear, an upper, a lower, a right and a left surface and a recess formed in the lower surface; a contact accommodated in the recess of the housing so as to extend from the rear surface side toward the front surface side; a lance block that is accommodated in the recess of the housing from the lower surface side to primarily lock the contact; and a side retainer that is accommodated in the recess of the housing from the lower surface side to secondarily lock the contact.
Due to the configuration described above, the connector disclosed in Japanese Patent Laid-Open No. 2007-324049 can provide a sufficient contact holding force even though the wall thickness of the housing is reduced to reduce the vertical and horizontal dimensions. In this specification, as in Japanese Patent Laid-Open No. 2007-324049, a body that primarily locks a contact is referred to as a lance, and a body that secondarily locks the contact is referred to as a retainer.
However, the lance block and the side retainer of the connector disclosed in Japanese Patent Laid-Open No. 2007-324049 are positioned side by side in the recess in the lower surface of the housing with the lower surfaces thereof exposed at the bottom of the housing. The lance block and the side retainer are satisfactorily locked even with such a configuration. However, the connector should be further improved in security if it is used in an automobile or the like.
A reason why the security should be further improved is because there is still an undeniable possibility that a relatively high impact exerted on the connector during use might force the lance block or the side retainer out of their respective normal positions in the housing. Besides, there are gaps between the lance block and the side retainer positioned side by side in the recess of the housing, between the housing and the lance block and between the housing and the side retainer, and foreign matters can enter the connector through the gaps.